AUTHOR=Said Rihan , Goda Rayan , Abdalrahman Ihab B. , Erwa Nahla H. H. 

TITLE=Case report: Insulin desensitization as the only option for managing insulin allergy in a Sudanese patient

JOURNAL=Frontiers in Allergy

VOLUME=Volume 4 - 2023

YEAR=2023

URL=https://www.frontiersin.org/journals/allergy/articles/10.3389/falgy.2023.1089966

DOI=10.3389/falgy.2023.1089966

ISSN=2673-6101

ABSTRACT=Introduction: Allergic reactions to insulin have become very rare with the introduction of human insulin. Anaphylaxis is a life-threatening condition that results from immediate IgE-mediated hypersensitivity. Desensitization to human insulin was reported to control immediate hypersensitivity reactions to insulin. Here we, describe the history and challenges in managing our patient, and the development of an insulin desensitization protocol in a resource-limited setup.
Case Summary: A 42-years old Sudanese lady with poorly controlled type 2 diabetes on maximum antidiabetic medications, required insulin therapy to achieve reasonable glycemic control. She developed progressive and severe immediate hypersensitivity reactions to insulin including anaphylaxis. Her condition was difficult to control using previously described treatment modalities. Serum sample analysis demonstrated insulin-specific IgE antibodies. Given her poor control and the fact that this lady was planned for breast surgery indicated insulin desensitization.  
A multi-disciplinary team was formed including the treating endocrinologist, clinical immunologists, intensive care consultant and intensive care team. A 72-hour desensitization protocol was developed by the clinical immunology team followed by in-house training on the preparation of insulin, within the hospital laboratory department, also in addition to the pre-booking of an ICU bed to undertake the desensitization. Following successful desensitization, and 24-hours observation, our patient was discharged on pre-meal human insulin which was well-tolerated.
Conclusions: Although insulin allergy is rare, once encountered; it is very challenging in patients who have no other treatment options available. Different protocols for insulin desensitization are described in the literature; the agreed protocol was implemented successfully achieving insulin desensitization in our patient despite the limited resources.